Need help with match_tool predicate in block loot tables

I'm trying to alter coal ore so that it only drops coal if mined with a stone pickaxe or greater. I'm trying to use the match_tool condition with a predicate using a tag, with the resource locator pointing to a tag containing every pickaxe other than the wooden one. Instead, no pickaxes drop coal when mining coal ore. I was able to do this with a predicate using an items list, but I'm not sure where I'm going wrong with tags. I've attached a screenshot of the contents of the tag "coal.json" in the directory "tags/items/mineable/coal", and the relevant bit in the loot table. Thanks!